steering grabs and pulls you to one side or another. not out of alignment or whole vehicle. its just a quick grab of the steering wheel. Does not matter what speed you are going
Get the truck to a mechanic immediately!
This is a severe safety item. If this is a 4wd SUV, it may very wheel be a problem with the front drive axle. 2WD or 4WD, it may be a wheel bearing problem. Or it could be something else.